The present invention is related to a side cover of a roller blind frame rail for closing an opening of a tail end of the roller blind frame rail.
A conventional roller blind frame rail has two ends each formed with an opening. In general, two side covers are respectively fitted with the two ends to close the openings. When fixing the roller blind on an inner window frame or an outer window frame, it is necessary to first fix a fixing seat on a suitable portion of the inner window frame or outer window frame for fixing the roller blind frame rail. Then the roller blind can be mounted. However, the inner window frame or outer window frame generally has different plane faces for locking the fixing seat thereon. Therefore, when changing the installation position of the conventional roller blind, many different fixing seats are needed for fixing the roller blind. This leads to waste and makes it inconvenient to install the roller blind.